Crude petroleum has traditionally been used as a primary source for raw materials for producing numerous specialty chemicals. Particular specialty chemicals that can be produced from the petrochemical raw materials include fatty alcohols. Fatty alcohols have many industrial and commercial uses. For example, fatty alcohols act as surfactants which are useful in personal care and household products, such as detergents. Fatty alcohols are also used in waxes, lubricating oils, cosmetics and solvents. The longer chain fatty alcohols may be used for transportation fuels such as diesel and jet fuels. However, obtaining fatty alcohols from crude petroleum requires a significant amount of energy and involves the use of a non-renewable energy source.
Further, even those fatty alcohols that are obtained from renewable sources such as from plant or animal derived fatty acids generally are prepared using a hydrogenation step. Hydrogenation is a costly process step but is utilized to eliminate the double bonds of unsaturated fatty acids. A number of prior art references disclose genetically engineered microorganisms that produce products including fatty acid derivatives such as fatty acid esters and fatty alcohols. For example reference is made to international application publications WO2007/136762; WO2008/119082; WO2010/075483; WO2011/008535 and WO2011/019858; U.S. Pat. No. 6,143,538 and U.S. Pat. No. 8,110,670; and U.S. Patent Pub. Nos. US2012/0115195 and US2012/0142979.
However, a need still exists in the field for improved fatty alcohol production from bioengineered microorganisms that is efficient, cost effective and further tailored for use in particular industrial applications. In addition, for certain industrial applications, it is desirable to have a high degree of saturation because the presence of one or more double bonds in a fatty alcohol may lower the melting point, reduce the shelf-life and/or reduce the heat stability of the compound. Therefore, compositions and methods that provide products having increased saturation levels in fatty alcohols and/or fatty alcohol derivatives are commercially beneficial.